/Engine/Plugins/Runtime/SmartObjects/Source/SmartObjectsModule/Public/SmartObjectTypes.h
The struct can also be used to be added to a Smart Object slot when it gets claimed. e.g. Claim(SlotHandle, FConstStructView::Make(FSmartObjectActorUserData(Pawn)));
[USTRUCT](Programming/UnrealArchitecture/Reference/Structs)() struct FSmartObjectActorUserData
TWeakObjectPtr<...
UserActor